Bio-based building blocks, case study of a large-scale manufacturing process
Bio-based chemicals are gaining interest as alternatives or additional sources of chemicals. Among them, organic acids are promising as building blocks and chemical platforms. To integrate the chemical industry supply chain, bio-based products must become commodity products and meet current specifications applied to petro-based chemicals in terms of quality and purity. This article will illustrate several purification challenges that manufacturers encounter by describing an industrial manufacturing process for citric acid production from fermentation to purification. Each step will be reviewed and explained with special emphasis on the continuous chromatography step based on acid retardation since it is the core operation unit of the described purification process.
Worldwide, over 400 billion dollars are generated every year from biomass including chemicals, pharmaceuticals, fuels, detergents, grease, and paint (1). Arguments in favor of a switch from petrochemical feed stocks to alternative ones such as bio-based chemicals are now well-known. First of all, the volatility of oil and gas prices remains high; while access to these resources implies a certain risk, and the impact of the greenhouse effect is still a reality. Secondly, bio-based chemicals production has a better carbon footprint and can rely on local feed stocks. Lastly, the hardening of environmental policy discourages activities that produce greenhouse effect gas. However, bio-based chemicals are not intended to replace petrochemicals, but repres